vsi-lldb: Update README with release tags
vsi-lldb: Update README with release tags

Added information about using the tag corresponding with SDK
release to build instructions. HEAD relies on HEAD version of
internal DLLs that are shipped with the SDK and therefore not
always compatible.

GitOrigin-RevId: 164eeb2d5afa34be00bd9fd2268beb2fb9a23da7

googlestadia/vsi-lldb,googlestadia/vsi-lldb,googlestadia/vsi-lldb